Care & Maintenance

In horticulture we use the collective term "ornamental grasses" to describe true grasses, sedges, rushes, reeds and some grass-like plants. It is important to distinguish between these groups if you wish to maintain them successfully.

Grasses, sedges, rushes and reeds have flowers, but not in a form recognisable to the majority of gardeners. They have no coloured petals and only a botanist with a hand lens or microscope would be able to identify the components of the flowers.

The commonly named 'Black Grass' [Ophiopogon planiscapus 'Nigrescens'] reveals it is not a grass when it produces little pink flowers followed by dark purple berries.

True Grasses

Generally speaking true grasses grow from their tips and can cope with being mown. The stems of deciduous grasses will either disintegrate in winter [e.g. Deschampsia, Molinia & Panicum] or they should be cut down in early spring [e.g. Miscanthus & Calamagrostis].

Miscanthus stems [left] should be cut down with secateurs as soon as new shoots get to about 10cm [4 inches] in height.

Calamagrostis [above right] require far less precision. Shears are the quickest way to cut down old stems.

Evergreen grasses such as Festuca glauca cvs. benefit from tidying up in spring by combing out or splitting to rejuvenate them every three or four years. If you cut them down in error they will not die, but the shaving brush effect is not pretty.

Sedges & Wood Rushes

Sedges [Carex] and wood rushes [Luzula] grow from the base and best practice in spring is to cut out tired and damaged leaves close to the ground. Unlike true grasses trimmed leaves will die at the ends and look very unattractive.

Propagation

Most of our perennial ornamental grasses are propagated by division. A few we produced from cuttings or seed.

Warm season grasses

Miscanthus, Panicum and Pennisetum are categorised as "warm season grasses" should be spit in May, June and July.

Cool Season grasses

Sedges and grasses are described as "cool season" and can be split in the autumn. We find it more practical to divide them in early spring, when conditions are favourable for growth. Calamagrostis and Molinia are in this category.